There is an urgent need for a long-term in vivo glucose-monitoring device for diabetes therapy. Diabetes is currently believed to afflict over 100 million people worldwide and nearly 18 million in the United States. In the U.S. this disorder, along with its associated complications, is ranked as the seventh leading cause of death. Research indicates that these long-term complications can be minimized in diabetics if blood glucose levels are maintained as near normal levels (60-110 mg/dL) as possible, so called "tight" glucose control. The integration of continuous glucose monitor readings into an automatic insulin pump control algorithm may substantially increase both the safety and effectiveness of insulin therapy in diabetics. BioTex, Inc. has developed a superior fluorescence affinity glucose sensor which is one of the most promising technologies currently being pursued for application in diabetes research and therapy. The objective this Phase II proposal is to commence human clinical studies with the sensor under an investigational device exemption (IDE) from the FDA. The anticipated outcome will be a thorough characterization of the optimal implantation, instrumentation, and use of the sensor in humans and refinements of the associated accessories and procedures. At the end of this project we will be poised to commence larger human clinical trials in support of a pre-market approval (PMA) application to the FDA for marketing a 3-5 day implantable continuous glucose sensing system. PUBLIC HEALTH RELEVANCE: BioTex, Inc. has successfully developed a minimally-invasive fluorescence affinity sensor (FAS) for continuous glucose monitoring over 3-5 days. The FAS has a number of advantages over currently available short-term implantable glucose sensors and is expected be a significant tool for diabetes research and therapy. Diabetes currently afflicts over 100 million people worldwide and nearly 18 million in the United States, and this disorder, along with its associated complications, is ranked as the seventh leading cause of death.